Retrieving a set of randomly chosen records (Oracle 9i)

Hi,

I need to analyze the data of very large tables (over 10 million records). Therefore I want to retrieve a set of randomly chosen records (about 50,000).

Question: Exists a predefined function in Oracle 9i, which fetches a certain part (e.g. 1%) of the rows of a table?

Hint: Because I need to get all of the data in a random order and not in the way the rows are arranged in the table I cannot work with SELECT * from xxx WHERE ROWNUM < 50001.
But maybe the ROWID can be utilized to fetch a random sample of the rows?

King regards,

Andreas Received on Fri Feb 18 2005 - 08:16:55 CST